Abstract：
Leishmania infection of macrophages results in altered Ras isoforms expression and Toll-like receptor-2 (TLR2) expression and functions. Therefore, we examined whether TLR2 would selectively alter Ras isoforms\' expression in macrophages. We observed that TLR2 ligands- Pam3CSK4, peptidoglycan (PGN), and FSL- selectively modulated the expression of Ras isoforms in BALB/c-derived elicited macrophages. Lentivirally-expressed TLR1-shRNA significantly reversed this Ras isoforms expression profile. TLR2-deficient L. major-infected macrophages and the lymph node cells from the L. major-infected mice showed similarly reversed Ras isoforms expression. Transfection of the macrophages with the siRNAs for the adaptors- Myeloid Differentiation factor 88 (MyD88) and Toll-Interleukin-1 Receptor (TIR) domain-containing adaptor protein (TIRAP)- or Interleukin-1 Receptor-Associated Kinases (IRAKs)- IRAK1 and IRAK4- significantly inhibited the L. major-induced down-regulation of K-Ras, and up-regulation of N-Ras and H-Ras, expression. The TLR1/TLR2-ligand Pam3CSK4 increased IL-10 and TGF-β expression in macrophages. Pam3CSK4 upregulated N-Ras and H-Ras, but down-regulated K-Ras, expression in C57BL/6 wild-type, but not in IL-10-deficient, macrophages. IL-10 or TGF-β signaling inhibition selectively regulated Ras isoforms expression. These observations indicate the specificity of the TLR2 regulation of Ras isoforms and their selective modulation by MyD88, TIRAP, and IRAKs, but not IL-10 or TGF-β, signaling.
摘要：
利什曼原虫感染巨噬细胞导致Ras亚型表达和Toll样受体2(TLR2)表达和功能改变。因此,我们检查了TLR2是否会选择性改变巨噬细胞中Ras亚型的表达。我们观察到TLR2配体-Pam3CSK4，肽聚糖（PGN），和FSL-选择性调节BALB/c-衍生的诱导巨噬细胞中Ras同种型的表达。慢病毒表达的TLR1-shRNA显著逆转了该Ras同种型表达谱。TLR2缺陷型主要乳杆菌感染的巨噬细胞和来自主要乳杆菌感染的小鼠的淋巴结细胞显示出类似的逆转的Ras亚型表达。用siRNAs转染巨噬细胞-髓样分化因子88（MyD88）和含有Toll-白介素-1受体（TIR）结构域的衔接蛋白（TIRAP）-或白介素-1受体相关激酶（IRAKs）-IRAK1和IRAK4-显着抑制L.major诱导的K-Ras下调，以及N-Ras和H-Ras的上调，表达式。TLR1/TLR2-配体Pam3CSK4增加巨噬细胞中IL-10和TGF-β的表达。Pam3CSK4上调N-Ras和H-Ras,但下调了K-Ras,在C57BL/6野生型中的表达，但不是缺乏IL-10，巨噬细胞。IL-10或TGF-β信号传导抑制选择性调节Ras亚型表达。这些观察结果表明，通过MyD88，TIRAP，和IRAKs,但不是IL-10或TGF-β，信令。
